In order to better realize the deep space optical communication under different conditions of background light and atmospheric turbulence,this paper compares two deep s pace channels of the receiving scheme models.The first scheme is the traditional receiving scheme,the photon detector array is placed directly on the focal plane of the antenna,and a pinhole diaphragm is added in front of the photon detector array.The second scheme is the improved receiving scheme,the pinhole diaphragm is placed on the focal plane,the optical signal passes through the diaphragm and then reaches the detector array through the col limating mirror.Firstly, atmospheric turbulence model and background light model are established,and thei r effects on receiver are analyzed.Then the aperture size of the aperture is optimized,finally the perfo rmance of the two receiving schemes is compared with the optimal aperture.The simulation results show that the optimal aperture is different in different atmospheric turbulence and background light,which can provide some re ference for the subsequent design of ground receiving system.The performanc e in the second scheme is also improved under different backgrounds and atmospheric turbulence,especially in strong backgroun d and atmospheric turbulence.